Cheap OCP Mezzanine cards to standard PCIE

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yaoyuanzy

New Member
Jan 15, 2020
2
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3
This thread is posted in order to pay back our fourms, beacuse the Inspiration comes from here. Will give us a new choice with Two port SFP+ 10GB Ethernet card,cheap and easy !








This thread tell you how to use a transfer suit to get a cheap 10GB Ethernet card,and a little work to change it
to brother model cx342a with two 10GB port!
1.use OCP to PCIE transfer suit Assembly with cx341a ocp card and put in windows or linux PC


2.OS will Recognized CX341A card with 1 Port 10GB,then we need change fw to cx342a at first.
Thanks to Mellanox,it's very easy to change fw in ConnectX-3!

Please allow me only post windows10 powershell Command,linux is basically the same.
Code:
2.1.download Mellanox drivers and tools,install it with default options
http://content.mellanox.com/MFT/WinMFT_x64_4_13_3_6.exe
http://content.mellanox.com/WinOF/MLNX_VPI_WinOF-5_50_52000_All_win2019_x64.exe
2.2 download file from http://share.homecc.win/pic/341a-fw.tgz  and decompress it to C:\Program Files\Mellanox\WinMFT,open poweshell  we will start it.
cd "C:\Program Files\Mellanox\WinMFT"
###check device info and record mac address
flint -d /dev/mst/mt4099_pci_cr0 q
###backup old flash,include fw and conf....
flint -d /dev/mst/mt4099_pci_cr0 rb 0 2097152 341a-cxen.bin
###write zero to flash
flint -d /dev/mst/mt4099_pciconf0 wb zero.bin 0
###write mellanox mcx342a fw to you ocp card,Notice XCC is work with hardware ver CX341A-XCAN to XCEN
flint -d /dev/mst/mt4099_pciconf0 --yes -i xcc.bin -mac f452149d2d14 --nofs b
#change mac address with before record‘s info,when flash done,you need reboot and will found two ports are Recognized by os,but is not Complete!


3 hardware change,you need Electronic welding tools
3.1 add sfp+ socket and shiled,is easy
3.2 use two 4.7uh inductance fill in pcb below c138 and c139, check the picture
3.3 use 1 yellow and 1green 0603 led fill in to pcb D4 and D2


ALL done,put it back to PC and check now CX342A is working now,iperf is used to check network performance test and stable test,you can use a scripts to start auto test and record result.
###PS C:\Program Files\Mellanox\WinMFT> .\mlxfwmanager.exe
Querying Mellanox devices firmware ...

Device #1:
----------

Device Type: ConnectX3
Part Number: MCX342A-XCC_Ax
Description: ConnectX-3 EN NIC for OCP;10GbE;dual-port SFP+;PCIe3.0 x8;IPMI disabled;R6
PSID: MT_1680110023
PCI Device Name: mt4099_pci_cr0
Port1 MAC: f452149d2d14
Port2 MAC: f452149d2d15
Versions: Current Available
FW 2.42.5000 2.42.5000
FW (Running) 2.31.1602 N/A
PXE 3.4.0752 3.4.0752
UEFI 14.11.0045 14.11.0045

Status: Up to date
 
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Alfa147x

Active Member
Feb 7, 2014
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Wow. This is very cool. Great work!

I like that you still maintained the LP height.
 

devrand

New Member
Apr 29, 2020
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Did anyone buy from taobao/1688?
I'd be interested into 2-5 adapter PCBs but ordering from those sites is just a hassle.
Otherwise I might just order PCBs from JLCPCB myself.
 

vsicth12

New Member
Sep 25, 2020
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1
Count me in for a group buy from JLCPCB. I have a Chelsio 100g OCP card that I'd like to convert to PCIe.
 

devrand

New Member
Apr 29, 2020
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The problem I found was that the OCP connectors are quite expensive, like 6€ per piece or so
 

MK_one

New Member
Feb 9, 2018
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Sadly the Pictures are down , can you upload them again ?
I bought two cards via Ebay , the OCP to Pcie Adapter was included for 18-20 Dollar each , that was last year and as it seem they sold all , i cant find it anymore , it says Mellanox MCX 311 on the Picture but was a 341A with OCP to PCIe Adapter which was confirmed by the seller as i asked for it
s-l140.jpg
 

prdtabim

Active Member
Jan 29, 2022
170
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Sadly the Pictures are down , can you upload them again ?
I bought two cards via Ebay , the OCP to Pcie Adapter was included for 18-20 Dollar each , that was last year and as it seem they sold all , i cant find it anymore , it says Mellanox MCX 311 on the Picture but was a 341A with OCP to PCIe Adapter which was confirmed by the seller as i asked for it
View attachment 22821
A new option using mezzanine cards. The price is acceptable.
 

MK_one

New Member
Feb 9, 2018
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A new option using mezzanine cards. The price is acceptable.
If i wanted to buy 10 Gbit Ethernet NIC i rather would buy this Mcx353a-qcat Mellanox ConnectX - 3 Infiniband 10 GigE Single port QSFP + Karte cx353a | eBay
Its only 10 Gbit Ethernet but if you connect two cards of them (MCX353A ) via Infiniband and use QSFP connections then it goes up to 56 Gbit and the chipcooler is better /bigger and you have no compatibility Problems from the Adapter . But i have already two 341A cards and Truenas Core not really supports Infiniband and with HDDs in your NAS you not really need more than 10 Gbit . If i would live in the USA i would consider to buy 2 cards anyway but to the 25 Dollars for a card would be added 16 Dollars Transport costs and 12 Dollars on import fees . Thats a bit much for not really using it.
I have bought now the parts for mod the 341A to a Dualport card , i will give it a try , it was ~ 11 Dollar , but it will take Time , the parts come from china.
 

MK_one

New Member
Feb 9, 2018
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it worked , even without the leds ( i ordered the wrong Type ) , i modified the flint command to
flint --allow_psid_change --allow_rom_change -d /dev/mst/mt4099_pciconf0 --yes -i xcc.bin -mac f452149d2d14 --nofs b
This allows flint to ignore the different psid of the Dual port 342A image .
I now have 2 working SFP+ ports on my fomer 341A
EDIT : the new port seems to work only with copper cables , Fiber + Transceiver dont work , i guess its only a configuration Problem , the second port did not exist so it lacks the list of compatible Transceiver in rom .
 
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